Steam Reforming of Methane Rich Gas in a Solar Reactor

A common route for hydrogen production is steam reforming of natural gas (NG) or other hydrocarbon materials. Using solar energy, the demand for fossil fuels and therefore CO{sub 2}- emissions can be reduced up to 40 % compared with conventional steam reforming processes for producing hydrogen. This paper presents recent achievements on innovative solar steam reforming technology. The solar reforming was successfully demonstrated in the SOLASYS project, supported by the European Commission in the JOULE/THERMIE framework. A pilot plant was built in the 3 MW solar facility at the Weizmann Institute of Science (WIS) in Israel. The reforming process comprises a pressurised volumetric receiver reactor (VRR) - the reformer. This unit is designed for a maximum gas outlet temperature of about 825 degrees C at 10 bar (absolute pressure) and absorbed solar power of about 400 kW. Rhodium (Rh) is used as a catalyst. Because NG is not available on site, Liquid Petroleum Gas (LPG) is used as a feedstock. This leads to additional system components such as evaporator, gas treatment, purifier, and pre-reformer which produce a feed gas containing primarily methane. Results of solar reforming tests at a solar power range of 100-220 kW, which is absorbed by the gas mixture, are presented. Synthesis gas was produced from a methane rich gas originated from the LPG and steam up to 9 bar and 765 degrees C with a conversion rate close to chemical equilibrium. (authors)